Learn Finnish: Me kiinnitämme turvavyöt, ennen kuin laskeutuminen alkaa. - We fasten our seatbelts before the landing starts.

In Finnish, a comma must separate the main clause (Me kiinnitämme turvavyöt) from the subordinate clause. Clauses starting with conjunctions like ennen kuin, koska, or että always require a comma before them.

Does ennen kuin change the word order of the clause that follows it?

No, it doesn't. The clause after ennen kuin keeps standard Subject-Verb word order. Here, the subject laskeutuminen (the landing) comes first, followed by the verb alkaa (starts).

Why is the object turvavyöt in its basic plural form? Don't objects normally get a special ending?

When a plural word is the total object of a sentence, it takes the plural nominative form, which is just the basic dictionary form plus the plural -t. It looks exactly like a normal plural subject! Only singular total objects get a special ending like -n.

How is the word laskeutuminen (landing) formed?

It is created by taking the verb laskeutua (to land or descend) and adding the -minen suffix to turn it into a noun. This functions very much like adding '-ing' to a verb in English.